Branches Of Internal Carotid Artery Research Articles

Preoperative Embolization of Primary Juvenile Nasopharyngeal Angiofibroma: Is Embolization of Internal Carotid Artery Branches Necessary?

To determine the effects of blood supply from internal carotid artery (ICA) on the surgical outcomes of primary juvenile nasopharyngeal angiofibroma (JNA) after transarterial embolization (TAE). A retrospective analysis was performed on primary JNA patients who underwent TAE and endoscopic resection in our hospital between December 2020 and June 2022. The angiography images of these patients were reviewed, and then they were divided into ICA + external carotid artery (ECA) feeding group and ECA feeding group according to whether the ICA branches were part of the feeding arteries. Tumors in ICA + ECA feeding group were fed by both ICA and ECA branches, while tumors in ECA feeding group were fed by ECA branches alone. All patients underwent tumor resection immediately after ECA feeding branches embolization. None of the patients underwent ICA feeding branches embolization. Data on demographics, tumor characteristics, blood loss, adverse events, residual and recurrence were collected, and case-control analysis was performed for the two groups. Differences in characteristics between the groups were tested using Fisher's exact and Wilcoxon tests. Eighteen patients were included in this study: nine in ICA + ECA feeding group and nine in ECA feeding group. The median blood loss was 700mL (IQR 550-1000mL) in ICA + ECA feeding group versus 300mL (IQR 200-1000mL) in ECA feeding group, with no significant statistical difference (P = 0.306). Residual tumor was found in one patient (11.1%) in both groups. Recurrence was not observed in any patient. There were no adverse events from embolization and resection in either group. The results of this small series suggest that the presence of blood supply from ICA branches in primary JNA has no significant effect on intraoperative blood loss, adverse event, residual and postoperative recurrence. Therefore, we do not recommend routinepreoperative embolization of ICA branches. Level 4, Case-control.

Embolization of Skull Base Meningiomas with Embosphere Microspheres: Factors Predicting Treatment Response and Evaluation of Complications

Preoperative embolization for intracranial meningiomas can cause tumor necrosis, reduce intraoperative blood loss, and facilitate surgery. This study aimed to evaluate the efficacy of tumor embolization using Embosphere microspheres for skull base meningiomas and analyze postembolization plain computed tomography (CT) and magnetic resonance imaging (MRI) scans to identify findings that could potentially predict treatment response. Between April 2014 and April 2020, 80 patients with skull base meningiomas presenting at our medical center underwent embolization with Embosphere microspheres. The effects of tumor embolization were evaluated through a comparison of postembolization plain CT and contrast-enhanced MRI. A total of 143 vessels (102 of 108 external carotid artery branches and 41 of 65 internal carotid artery branches) from 80 skull base meningiomas were embolized with Embosphere microspheres. Microspheres 100-300 μm in size were used in 2 cases, microspheres 300-500 μm in size were used in 12 cases, and microspheres 500-700 μm in size were used in 66 cases. Postembolization contrast-enhanced MRI showed reductions in enhancing lesions within the tumor in 55 of 80 cases. Postembolization plain CT scans showed high-density lesions within the tumor in 41 of 55 cases. Thus, reductions in enhancing lesions on postembolization contrast-enhanced MRI were statistically significantly associated with the presence of high-density lesions on postembolization plain CT (P < 0.001). Embolization-related neurological complications occurred in 3 cases. Embosphere microspheres are user friendly and effective embolic materials for the embolization of skull base meningiomas. Postembolization contrast-enhanced MRI and plain CT findings may be useful for evaluating the effects of tumor embolization.

Identifying feeding artery during preoperative embolization of juvenile nasopharyngeal angiofibroma

Treatment of choice and standard of care is surgical resection of the tumor. Nasopharyngeal angiofibromas receive an abundant blood supply mainly from the external carotid branches and partly from the internal carotid artery branches. Many patients are treated with preoperative embolization to minimize the risk of intraoperative hemorrhage and related complications . This retrospective study, we obtained analysis of the medical and imaging records of 11 patients with pathologically proven juvenile nasopharyngeal angiofibroma. Who we performed preoperative endovascular embolization between January 2019 until Desember 202 in Wahidin Sudirohusodo Hospital, Makassar, Indonesia. The procedure was carried out using a cathlab monoplane Philips. A total 11 patients (only 1 female) with juvenile nasopharynx angiofibroma underwent endovascular embolization from 2019-2021 in Wahidin Sudirohusodo Hospital Makassar. Arteriography examination in patients with angiofibroma tumors revealed that the feeding arteries originate from the internal maxillary artery, ascending pharyngeal artery, fascial artery, middle meningeal artery and branches of the internal carotid artery. Identifying the feeding artery before embolization is very important to facilitate the embolization process

Fetal posterior communicating artery as a conduit for concurrent anterior and posterior circulation infarct: A case report

Fetal type posterior cerebral artery (FTPCA) is a variant of posterior circulation of brain, in which the distal part of posterior cerebral artery (PCA) is perfused by a branch of internal carotid artery (ICA) via fetal posterior communicating artery (fetal PCOM). In the presence of fetal PCOM, a paradoxical concurrent infarction of anterior and posterior circulation may happen. We report a 67-year-old man who presented with sudden onset right sided weakness and aphasia, with National Institutes of Health Stroke Scale (NIHSS) score of 22 and clinically diagnosed to have left total anterior circulation infarct (TACI). Subsequently, he received IV Alteplase as a standard hyperacute ischemic stroke treatment. Computed tomography angiography (CTA) of brain showed left FTPCA with prominent left fetal PCOM. Subsequent computed tomography (CT) of brain showed concurrent left middle cerebral artery (MCA) and PCA territories infarct. CTA brain is commonly done in ischemic stroke cases to assess presence of large vessel occlusions and intracranial or extracranial atherosclerotic disease. However, this case depicts its additional role in detecting anatomical variants of cerebral circulation. In terms of clinical importance, presence of multiple territories infarction portends a poorer neurological outcome.

Blood Supply of Cranial Nerves Passing Through the Cavernous Sinus: An Anatomical Study and Its Implications for Microsurgical and Endoscopic Cavernous Sinus Surgery.

BackgroundDespite improvements in surgical techniques, cranial nerve (CN) deficits remain the most frequent cause of disability following cavernous sinus (CS) surgery. The most common tumor affecting the CS is meningioma. They originate from lateral wall and have their blood supply from meningohypophyseal trunk (MHT) and inferolateral trunk (ILT). Pituitary adenomas commonly invade the CS through its medial wall and receive blood supply form medial branches of the internal carotid artery (ICA) (superior and inferior hypophyseal arteries). Some tumors may grow within the CS (e.g. trigeminal schwannomas, hemangiomas). These tumors are fed by all the intracavernous ICA branches. Tumors involving the CS may also displace the neurovascular structures, therefore, a better understanding of intracavernous neurovascular anatomy may reduce the postoperative morbidity associated with approaching CS tumors. In this anatomical study, the anatomic variations and their clinical implications of the intracavernous CNs’ blood supply were evaluated through transcranial and endonasal routes.MethodsTwenty sides of ten adult cadaveric formalin-fixed, latex-injected specimens were dissected in stepwise fashion under microscopic and endoscopic magnification. The origin and course of the intracavernous ICA branches supplying the intracavernous CNs are studied.ResultsThe proximal segment of the oculomotor nerve receives blood supply from the ILT in 85%, and the tentorial artery of the MHT in 15% of specimens. The distal segment is exclusively supplied by the ILT. The proximal trochlear nerve receives blood supply from the ILT (75%) and the tentorial artery (25%); the distal segment is exclusively supplied by the superior orbital branch. The proximal third of the abducens nerve receives its vascularity exclusively from the dorsal meningeal artery, and its middle and distal thirds from the ILT. The ophthalmic and proximal maxillary segments of the trigeminal nerve also receive blood supply from the ILT. The distal maxillary segment is supplied by the artery of the foramen rotundum. All ILT branches terminate on the inferomedial aspects of the intra-cavernous CNs. Extensive anastomoses are found between ILT branches and the branches arising from external carotid artery.ConclusionUnderstanding the anatomy of the intracavernous ICA’s branches is important to improving surgical outcomes with tumors involving the CS.

Pre-Operative Embolisation of an Aberrant Pharyngeal Arterial Branch Arising From the Internal Carotid Artery and Contributing Significantly to the Supply of a Large Juvenile Nasopharyngeal Angiofibroma

Preoperative embolisation of juvenile nasopharyngeal angiofibromas (JNAs) is a well-established treatment that reduces intraoperative blood loss and improves surgical outcomes. While the bulk of arterial supply to the tumour is derived from the external carotid system, some degree of contribution from the internal carotid artery (ICA) is common. ICA branch embolisation in this setting has previously been avoided due to concerns over ischaemic neurological complications, possibly contributing to the increased intraoperative blood loss observed in patients with tumours with ICA supply. There is a marked paucity of reports of embolisation of ICA branches supplying JNA in the medical literature. We present a case of successful embolisation of an aberrant pharyngeal branch of the ascending pharyngeal artery arising from the proximal cervical ICA, which was making a significant contribution to tumour blood supply in a male adolescent with a very large JNA.

Dural Arteriovenous Fistulas of the Foramen Magnum Region: Clinical Features and Angioarchitectural Phenotypes

AVFs of the foramen magnum region, including fistulas of the marginal sinus and condylar veins, have complex arterial supply, venous drainage, symptoms, and risk features that are not well-defined. The purpose of this study was to present the angioarchitectural and clinical phenotypes of a foramen magnum region AVF from a large, single-center experience. We retrospectively reviewed cases from a 10-year neurointerventional data base. Arterial and venous angioarchitectural features and clinical presentation were extracted from the medical record. Venous drainage patterns were stratified into 4 groups as follows: type 1 = unrestricted sinus drainage, type 2 = sinus reflux (including the inferior petrosal sinus), type 3 = reflux involving sinuses and cortical veins, and type 4 = restricted cortical vein outflow or perimedullary congestion. Twenty-eight patients (mean age, 57.9 years; 57.1% men) had 29 foramen magnum region AVFs. There were 11 (37.9%) type 1, nine (31.0%) type 2, six (20.7%) type 3, and 3 (10.3%) type 4 fistulas. Pulsatile tinnitus was the most frequent symptom (82.1%), followed by orbital symptoms (31.0%), subarachnoid hemorrhage (13.8%), cranial nerve XII palsy (10.3%), and other cranial nerve palsy (6.9%). The most frequent arterial supply was the ipsilateral ascending pharyngeal artery (93.1% ipsilateral, 55.5% contralateral), vertebral artery (89.7%), occipital artery (65.5%), and internal carotid artery branches (48.3%). We present the largest case series of foramen magnum region AVFs to date and show that clinical features relate to angioarchitecture. Orbital symptoms are frequent when sinus reflux is present. Hemorrhage was only observed in type 3 and 4 fistulas.

Dissection‐Based Investigation of Variations in Major Gross Arterial Supply to the Trigeminal Ganglion

Introduction & Objective The trigeminal nerve (CN V) primarily conveys afferent sensory input from the anterolateral aspect of the face and scalp via its three main branches – the ophthalmic nerve (CN V1), maxillary nerve (CN V2), and mandibular nerve (CN V3). The 20,000-35,000 primary afferent pseudounipolar neurons of CN V1-3 converge at the trigeminal ganglion (TG) where the neurons’ cell bodies are positioned. The TG is located in Meckel's cave (cavum trigeminale), an intracranial area along the sphenoid bone deep to the meningeal layer of dura mater just anterior to the petrous apex. Four main arterial sources have been reported to perfuse the TG – the accessory meningeal artery (AMA), a branch of middle meningeal artery (MMA), a branch of internal carotid artery (ICA), and a tentorial branch of the superior cerebellar artery (SCA). The reported rate for each potential arterial supply remains variable. The objective of this study was to identify the arterial source of the TG via human cadaveric dissection and quantify the rate of occurrence. Materials & Methods Right and left trigeminal ganglia were examined on 29 embalmed human cadavers. Origins of gross arterial supply traversing the deep surface of the ganglia were identified and recorded. Arterial supply was photographed (iPad Pro, Apple Inc.) and image color contrast was utilized to aide structure identification (Adobe Photoshop 20.0.9). TG tissue samples including the major vessel(s) were collected, paraffin embedded, sectioned at 5 μm, and stained with hematoxylin and eosin (H&E). Major arteries and normal microvasculature were verified with light microscopy (Zeiss Axioskop, Model 45 14 85) and photographed (AmScope Digital Camera, Model MU1003). Results Blood supply to 28 TG was inconclusive due to compromised vessel integrity from a previous course dissection. Of the remaining 30 TG, 56.6% were supplied by a branch of ICA, 16.7% by AMA, and 10.0% by a branch of MMA. No TG were supplied by the tentorial branch of SCA. Anastomotic connections were discovered between MMA/ICA and AMA/ICA for 10.0% and 6.7% of TG supply, respectively. Three of the five AMAs were noted to course through separate foramen in the basicranium instead of the foramen ovale as expected. H&E histological examination confirmed artery structure and verified expected arteriole and capillary microvasculature throughout the TG. Conclusions & Significance In both exclusive and anastomotic form, the majority of TG arterial supply originated from the ICA. Supply from the AMA, MMA, and SCA occurred less often but still merit significance. The results of this study reflect known rates of TG arterial supply. Gross imaging from this study may supply medical educators with new resources to facilitate TG dissection in gross dissection laboratories and may also provide diagnosticians and cardiovascular surgeons with better understanding of TG arterial supply variations that could benefit diagnosis, surgical approaches, and outcomes. In case of blockage, stenosis, or ligation, anastomotic supply would provide anatomical insurance to the TG but warrants further study.

COVID-19 and Stroke

Most patients with COVID-19 present with constitutional and respiratory symptoms and some with atypical gastrointestinal, cardiovascular, or neurological manifestations. Recent studies suggest that there are neurologic manifestations of COVID-19, including acute cerebrovascular disease (CVD). The aim of this study is to find out any evidence of COVID-19 related stroke. Radiologic studies of the patients admitted to the emergency department (ED) of our center from March 11 Th to June 10 Th 2020, with acute stroke symptoms and of whom the acute cerebrovascular disease is confirmed by Computed Tomography (CT) and/or Magnetic Resonance Imaging (MRI) are searched retrospectively. CT Angiography (CTA) and MR Angiography (MRA) studies obtained for stroke management, searched for acute thromboembolism. We noticed some radiologic evidence of acute cerebrovascular disease in 56 patients of 528 patients admitted with immediate neurological symptoms. 11 (19.64 %) of these patients who were not diagnosed before, proved to be simultaneous COVID-19 infection with laboratory tests and/or thorax CT. It was noteworthy that these 11 patients presented with an acute cerebrovascular event supported by neurological and radiological findings instead of the well-known constitutional or respiratory symptoms of COVID 19 infection. 45 (80.35 %) patients were negative for COVID-19 infection. CT /or MR Angiography demonstrated carotid or intracranial major arterial thromboembolism in 5 (11.1 %) of the non-COVID-19 patients and 5 (45.4 %) of the simultaneous COVID-19 disease diagnosed ones. COVID19 positive 5 patients presented with acute internal carotid artery (ICA) or major ICA branch thrombosis at the first stage of COVID-19 infection, rather than a complication of the serious lung disease or a component of multiorgan disfunction related COVID-19. Acute cerebrovascular disease symptoms bringing patients to the ED instead of the respiratory symptoms, aroused high suspicion of the direct neuropathy and early coagulopathy effect of the virus. COVID- 19 disease, itself thought to be a great risk factor for stroke alone. Even in initial cases and in cases where COVID-19 infection do not show a severe and fatal course, stimulation in the coagulation cascade in the early stages, increased the risk of acute stroke.

Study of variations in the anterior half of the circle of Willis using magnetic resonance angiography

The Circle of Willis is a cerebral arterial anastomosis uniting the internal carotid artery with the vertebro-basilar system. It has ten components namely- the two anterior cerebral arteries (branches of internal carotid arteries) connected by the anterior communicating artery anteriorly, and the two posterior cerebral arteries (branches of basilar artery) connected to the internal carotid arteries via the two posterior communicating arteries. The aim of this study was to study the variations in the formation of the anterior part of the circle of Willis using Magnetic Resonance Angiography (MRA), and to review the embryological and clinical perspectives. The study was conducted over 18 months in the department of Anatomy in collaboration with the department of Radio-diagnosis at Pushpagiri Institute of Medical Sciences and Research Centre, Tiruvalla. MRA study was performed on 215 images, which were obtained from the electronic database at the Department of Radio-diagnosis. All the circles were further categorized into complete and incomplete, and analyzed with regard to each of the components of the anterior part. In this study, it was observed that the entire circle was complete in approximately 62.79% of the total, the anterior part being complete in 200 images with 86 of them showing textbook configuration. The incidences of variations were observed to be higher on the right side than on the left. The most frequent variation was hypoplasia of A1 segment of ACA in the anterior part of the circle of Willis.

Study of variations in the posterior part of the circle of Willis using magnetic resonance angiography

The Circle of Willis is an arterial anastomosis uniting the internal carotid artery with the vertebro-basilar system. This cerebral arterial circle has ten components namely- the two anterior cerebral arteries, branches of internal carotid arteries, connected by the anterior communicating artery anteriorly, and the two posterior cerebral arteries, branches of basilar artery, connected to the internal carotid arteries via the two posterior communicating arteries. The aim of this study was to study the variations in the formation of the posterior part of the circle of Willis using Magnetic Resonance Angiography (MRA), and to review the embryological and clinical perspectives. The study was conducted over 18 months in the Department of Anatomy in collaboration with the Department of Radio-diagnosis at Pushpagiri Institute of Medical Sciences and Research Centre, Tiruvalla. MRA study was performed on 215 images, which were obtained from the electronic database at the Department of Radio-diagnosis. All the circles were further subdivided into complete and incomplete, both as a whole, and pertaining to the posterior parts, and analyzed. In this study, it was observed that the entire circle was complete in approximately 62-66% of the total, the posterior part being complete in approximately 66-76% of the total. The incidences of variations were observed to be higher on the right side than on the left. The most frequent variation was the partial foetal variant of posterior cerebral artery (PCA) in the posterior part of the circle of Willis.

Microsurgical Neurovascular Anatomy of the Brain: The Anterior Circulation (Part I).

Introduction:Treatment of cranial neurovascular pathology requires a detailed understanding of the brain, head, and neck vasculature. This study aims at a comprehensive overview of the microsurgical anatomy of the anterior cerebral circulation.Methods:Five formalin-fixed adult cadaveric heads were used. Common carotid arteries, vertebral arteries, and internal jugular veins were injected with colored latex (red for arteries and blue for veins). The heads were dissected under a surgical microscope with magnifications ranging between 3× to 40× focusing on the anterior circulation. A synoptic approach was used to describe in detail the segments, branches, perforating arteries, veins, and vascular territories of the cerebral arteries and veins.Results:The anterior arterial circulation of the brain is provided by the internal carotid artery (ICA), anterior cerebral artery (ACA), middle cerebral artery (MCA), anterior communicating artery (ACoA), and perforating arteries. Perforating arteries of the anterior circulation arise from the ICA, ACA, MCA, ACoA, and posterior communicating artery (PCoA). The distal segments and collateral branches of the ICA, ACA, and MCA give the arterial supply to the largest part of the forebrain, whereas perforating arteries of the anterior circulation are related to the striatum, thalamus, and basal ganglia. The ACoA is the core functional anastomosis between the left and right ICA systems. The external carotid artery provides the vascular supply to the region of the face, head, and neck, and most of the meninges. The internal jugular venous system is composed of the internal and external jugular veins, which constitutes the outflow of the cerebral and facial venous system, respectively.Conclusion:Thorough knowledge of the topographic, cisternal, and functional anatomy of the anterior circulation of the brain is critical for surgery of the supratentorial lesions. (www.actabiomedica.it)

Classification of internal carotid artery injuries during endoscopic endonasal approaches to the skull base.

Background: Internal carotid artery (ICA) injuries are a major complication of endoscopic endonasal approaches (EEAs), which can be difficult to manage. Adding to the management difficulty is the lack of literature describing the surgical anatomical classification of these types of injuries. This article proposing a novel classification of ICA injuries during EEAs.Methods: The classification of ICA injuries during EEAs was generated from the review of the literature and analysis of the main author observation of ICA injuries in general. All published cases of ICA injuries during EEAs in the literature between January 1990 and January 2020 were carefully reviewed. We reviewed all patients’ demographic features, preoperative diagnoses, modes of injury, cerebral angiography results, surgical and medical management techniques, and reported functional outcomes.Results: There were 31 papers that reported ICA injuries during EEAs in the past three decades, most studies did not document the type of injury, and few described major laceration type of it. From that review of the literature, we classified ICA injuries into three main categories (Types I-III) and six sub-types. Type I is ICA branch injury, Type II is a penetrating injury to the ICA, and Type III is a laceration of the ICA wall. The functional neurological outcome was found to be worse with Type III and better with Type I.Conclusion: This is a novel classification system for ICA injuries during EEAs; it defines the patterns of injury. It could potentially lead to advancements in the management of ICA injuries in EEAs and facilitate communication to develop guidelines.

Carotid-cavernous fistula from the perspective of an ophthalmologist A Review.

Carotid-cavernous fistula (CCF) is an abnormal communication - vascular connection between arteries and veins in the cavernous sinus. Classification according to etiology is traumatic vs spontaneous. According to blood flow rate per high flow vs low flow fistula. According to anatomy of direct vs indirect: Direct (direct) CCF arises through direct communication between the internal carotid artery (ICA) and the cavernous sinus. Indirect CCF originates through indirect communication through the meningeal branches of ICA, external carotid artery and cavernous sinus (not directly with ICA) and Barrow type A, B, C, D division. Patientssubjective complaints depend on the type of CCF. Most often it is pulsating tinnitus, synchronous with blood pulse. Typical findings include protrusion and pulsation of the eyeball, corkscrew vessels - arterialization of conjunctival and episleral vessels, increased intraocular pressure, not responding to local antiglaucomatous therapy, keratopathy alagophthalmo, corneal ulcers. In the later untreated stages of CCF, secondary, venous stasis or central retinal vein occlusion can occur. Diagnostic procedures include B-scan and color Doppler ultrasonography, digital ophthamodynamometry, computer tomography, nuclear magnetic resonance and digital subtraction angiography. CCF can simulate orbitopathy, conjunctivitis symptoms, carotid occlusion, scleritis or cavernous sinus thrombosis. The ophthalmologist should recognize and indicate the necessary examinations in atimely manner. The therapy is ophthalmological, neuroradiological, sterotactic, surgical and conservative.

Aberrant Extracranial Branch Prevents Internal Carotid Artery Occlusion

The internal carotid artery (ICA) is a terminal vessel that does not give rise to branches in the extracranial segment. The ICA occlusion typically extends to the first intracranial branch, the ophthalmic artery. We present a rare case of isolated ICA occlusion with distal patency due to an aberrant extracranial branch. A 52-year-old man with longstanding tobacco use, hypertension, hyperlipidemia, diabetes, and extensive coronary artery disease was referred to the vascular laboratory for evaluation of carotid disease. The patient had no history of transient ischemic attack (TIA), amaurosis fugax, or cerebrovascular accident. Carotid duplex results prompted further evaluation by computed tomography angiography (CTA). Duplex imaging demonstrated right common carotid artery (CCA) plaque with significantly elevated velocities and turbulent flow extending into the ICA. Mild heterogeneous plaque was noted proximally in the left ICA followed by less than 2-cm occlusion and reconstitution of flow in the distal extracranial segment. The CTA testing revealed a moderate right CCA stenosis, mild proximal left ICA plaque and an isolated occlusion of the mid-ICA and distal reconstitution via an aberrant collateral branch. The left intracranial ICA segment remained patent throughout its course but was of smaller caliber. Aberrant branches of the extracranial ICA are unusual and rarely identified by carotid duplex analysis. Awareness of this anomaly underscores the importance of determining patency of distal ICA flow in the presence of an occluded proximal segment; aberrant collaterals can make surgical exploration and endarterectomy in these patients feasible.

The 25th anniversary of the retrograde suction decompression technique (Dallas technique) for the surgical management of paraclinoid aneurysms: historical background, systematic review, and pooled analysis of the literature.

Paraclinoid internal carotid artery (ICA) aneurysms frequently require temporary occlusion to facilitate safe clipping. Brisk retrograde flow through the ophthalmic artery and cavernous ICA branches make simple trapping inadequate to soften the aneurysm. The retrograde suction decompression (RSD), or Dallas RSD, technique was described in 1990 in an attempt to overcome some of those treatment limitations. A frequent criticism of the RSD technique is an allegedly high risk of cervical ICA dissection. An endovascular modification was introduced in 1991 (endovascular RSD) but no studies have compared the 2 RSD variations. The authors performed a systematic review of MEDLINE/PubMed and Web of Science and identified all studies from 1990-2016 in which either Dallas RSD or endovascular RSD was used for treatment of paraclinoid aneurysms. A pooled analysis of the data was completed to identify important demographic and treatment-specific variables. The primary outcome measure was defined as successful aneurysm obliteration. Secondary outcome variables were divided into overall and RSD-specific morbidity and mortality rates. Twenty-six RSD studies met the inclusion criteria (525 patients, 78.9% female). The mean patient age was 53.5 years. Most aneurysms were unruptured (56.6%) and giant (49%). The most common presentations were subarachnoid hemorrhage (43.6%) and vision changes (25.3%). The aneurysm obliteration rate was 95%. The mean temporary occlusion time was 12.7 minutes. Transient or permanent morbidity was seen in 19.9% of the patients. The RSD-specific complication rate was low (1.3%). The overall mortality rate was 4.2%, with 2 deaths (0.4%) attributable to the RSD technique itself. Good or fair outcome were reported in 90.7% of the patients.Aneurysm obliteration rates were similar in the 2 subgroups (Dallas RSD 94.3%, endovascular RSD 96.3%, p = 0.33). Despite a higher frequency of complex (giant or ruptured) aneurysms, Dallas RSD was associated with lower RSD-related morbidity (0.6% vs 2.9%, p = 0.03), compared with the endovascular RSD subgroup. There was a trend toward higher mortality in the endovascular RSD subgroup (6.4% vs 3.1%, p = 0.08). The proportion of patients with poor neurological outcome at last follow-up was significantly higher in the endovascular RSD group (15.4% vs 7.2%, p < 0.01). The treatment of paraclinoid ICA aneurysms using the RSD technique is associated with high aneurysm obliteration rates, good long-term neurological outcome, and low RSD-related morbidity and mortality. Review of the RSD literature showed no evidence of a higher complication rate associated with the Dallas technique compared with similar endovascular methods. On a subgroup analysis of Dallas RSD and endovascular RSD, both groups achieved similar obliteration rates, but a lower RSD-related morbidity was seen in the Dallas technique subgroup. Twenty-five years after its initial publication, RSD remains a useful neurosurgical technique for the management of large and giant paraclinoid aneurysms.

Study of the effect of stenosis severity and non-Newtonian viscosity on multidirectional wall shear stress and flow disturbances in the carotid artery using particle image velocimetry

The development of atherosclerosis at the carotid bifurcation is impacted by local variations in wall shear stress (WSS) magnitude and direction, as well as flow complexity within the vessel. In this study, stereoscopic particle image velocimetry (PIV) was used to investigate multidirectional WSS and disturbed flow for idealized models of the carotid bifurcation with varying eccentric stenosis of the internal carotid artery (ICA) and both Newtonian (N-fluid) and non-Newtonian (nN-fluid) blood analogues. Turbulence intensity (TI) was reduced with the nN-fluid compared to N-fluid for mild to moderate stenosis, and comparable for more severely stenosed (70%) models. Differences in maximum TI due to viscosity model ranged from 0.02 m/s to 0.06 m/s compared to much larger differences due to geometry of up to 0.29 m/s between mild and severe stenosis. The level of time-averaged WSS (TAWSS) increased with stenosis severity from 5 Pa to 32 Pa, and nN-fluid led to higher WSS on average than N-fluid counterparts. Regions of elevated oscillatory shear index (OSI) demarcated recirculation regions, and mean OSI in the ICA branch was reduced for nN-fluid models by 9–19% compared to N-fluid. Transverse WSS (transWSS) increased with WSS magnitude and again was higher in nN-fluid models. Surface area exposure to shear metrics indicated that a Newtonian viscosity assumption predicted larger regions of low and oscillatory WSS, while predicting reduced regions of high transWSS, in comparison to the more physiological shear thinning fluid.

Digital Subtraction Angiography of Anterior Cerebral Artery Complex in Indian Population at Two Tertiary Super-Specialty Hospitals

Background: Cerebral circulation has different variations in blood supply. Anterior cerebral artery is an important terminal branch of internal carotid artery. It forms the anterior component of circle of Willis along with the anterior communicating artery. The knowledge of anatomical variations in anterior cerebral artery is of considerable help to clinicians.Objective: The purpose of the study is to find out common anatomical variations of anterior cerebral artery complex by digital subtraction angiography in Indian population.Methodology: This descriptive cross-sectional study was conducted in the Neurointervention department of Max Super-specialty Hospital, New Delhi and Neo Multi-specialty Hospital, Noida, India during July 2016 to December 2016 for a period of six (06) months. Patients admitted in the Neurointervention department for digital subtraction angiography (DSA) were included in this study. Sampling technique was purposive. The angiogram machine was SIEMENS Artis Zee system and framing rate was 4f/sec. Morphology and variations of the anterior cerebral arteries and the anterior communicating artery were studied in 75 patients undergone cerebral DSA.Results: Variations were found in 48% (n=36). Variations of the segments in relation with size, course, communications and terminations of the anterior cerebral artery (ACA) were noted. These were divided into different groups like hypoplasia, aplasia, duplication and fenestrations. Hypoplasia/Aplasia of proximal anterior cerebral artery (A1) was 13.3% in right side and 5.3% in left side. Anterior communicating artery (AComA) was found absent in 10.7% and fenestration in 12%. Callosomarginal artery was found absent in 1.3% in right side and 5.3% in left side. In right callosomarginal artery 6.8% had abnormal origin and 4.2% abnormal in left side. Pericallosal artery was present 100% on both sides.Conclusion: Variations of anterior cerebral artery complex anatomy is found common in Indian population. Among them hypoplasia/aplasia is most commonJournal of National Institute of Neurosciences Bangladesh, 2018;4(1): 12-17

Anomalous branches of internal carotid artery supplying large carotid body tumor

Anomalous branches of internal carotid artery supplying large carotid body tumor

Patency of the supraclinoid internal carotid artery branches after flow diversion treatment. A meta-analysis

Background and purposePlacement of flow-diverters across the ostia of major ICA branches carries a risk of arterial occlusion. We determined the rate of occlusion of the supraclinoid ICA branches and the related symptoms, following coverage with flow-diverters. Materials and methodsA systematic search was performed in PubMed, MEDLINE, and EMBASE. We selected studies reporting treatments with flow-diverters in which the device was placed across the ostium of the OphtA, PcomA, or AchorA. Random-effects meta-analysis was used to pool the following outcomes: rate of arterial occlusion, diminished flow, incidence of related symptoms, factors associated with arterial occlusion. ResultTwenty-one studies evaluating 1152 supraclinoid ICA branches were included in the meta-analysis. The incidence of OphtA occlusion and associated symptoms was 5.9% (95 CI% = 3.1–8.6%) (incidence rate = 6% per patient-year), and 0.8% (95% CI = 0.1–1.4%) (incidence rate = 0.8% per patient-year), respectively. Although asymptomatic in all cases, PcomA showed a higher occlusion rate (20.7%, 95% CI = 8.9–32.4%) (incidence rate = 19.5% per patient-year). AchorA was occluded in 1% (95% CI = 0.3–2.4%) of cases, with approximately 1% (95% CI = 0.4–2.3%) of transient neurological symptoms (incidence rate = 0.96% per patient-year). There was a trend toward higher odds of arterial patency among arteries arising from the aneurysm (OR = 2.94, P = 0.06). Demographic factors and multiple stents were not associated with higher risk of arterial impairment. Adequate collateral circulation was reported in 94.5% of patients with arterial occlusion. ConclusionsDuring aneurysm treatment, the ostium of the supraclinoid ICA branches can be covered with flow-diverter devices with low rates of neurological symptoms related to arterial occlusion.